Amazing stuff! Casablanca is not only famous for the same name 1942 movie (director Michael Curtiz, starring Humphrey Bogart and Ingrid Bergman)!
"Thanks to estimates for how long it would have taken for DNA differences to accrue, scientist have a good idea of when the last common ancestor (LCA) to modern humans—Neanderthals and Denisovans—lived: sometime around 765,000 to 550,000 years ago. But the identity of that LCA, and where it lived, have long been a mystery. A trove of fossils unearthed from a rock quarry in Morocco could shed light on the hominin that lived at this critical juncture in the story of human evolution.
Jawbones, teeth, and vertebrae discovered at the Grotte à Hominidés site have a mixed bag of derived and ancestral traits. The molars tapered toward the back of the mouth, and the lower surface of a vertebra was curved and inward-facing, like those of earlier hominins such as Homo erectus. Yet the shape and small size of wisdom tooth roots is a trait usually associated with Homo sapiens. The fossils were dated to around 773,000 years ago, close in time to when the LCA of humans, Neanderthals, and Denisovans would have lived.
Taken together, that’s suggestive evidence that these fossils may have come from close relatives of that LCA, though exactly where their species falls in the human family tree remains a mystery. Still, other researchers urged caution, noting that while the authors’ interpretation is plausible, the fossils’ mixture of traits could simply represent normal variation, not a true blend of old and new that would anchor it at the root of our species’ split with its close cousins."
"... But the identity of the last common ancestor of all three has long eluded scientists. And rather than imagining one progenitor species, a growing number of researchers now think populations in different regions mated intermittently and contributed to the ancestry of these three big-brained human types. “There probably wasn’t one population that gave rise to the human lineage. There probably were lots of populations in various places,” Schroeder says.
Well-dated fossils from that time span could help untangle things, but few have been found. One exception, a trove of remains from a species called H. antecessor, comes from a site known as Gran Dolina in Spain. Fossils there date to between 950,000 and 770,000 years ago. Some scientists think H. antecessor could be that last common ancestor, but its Spanish residency flies against the consensus in paleoanthropology that our species’ roots were in Africa. ..."
"... The site, also known as Grotte à Hominidés (“Hominid Cave”), has drawn the interest of scientists since 1969—when a partial jaw of a modern human relative was discovered, along with dental remains and a femur.
In the Nature study, the authors used high-resolution magnetostratigraphy, a sophisticated technique that can precisely date geological sequences, to confirm that the fossils are approximately 773,000 years old. ...
The results stem from over three decades of archaeological and geological research conducted under the Moroccan-French Program “Préhistoire de Casablanca.” This program conducts extensive excavations, systematic stratigraphic studies, and large-scale geoarchaeological analyses in the southwest part of the city of Casablanca. ...
As a result, the Casablanca region has become one of Africa’s richest repositories of Pleistocene palaeontology and archaeology, documenting the early Acheulean and its developments, diverse faunas reflecting environmental change, and several phases of hominin occupation."
From the abstract:
"Palaeogenetic evidence suggests that the last common ancestor of present-day humans, Neanderthals and Denisovans lived around 765–550 thousand years ago (ka). However, both the geographical distribution and the morphology of these ancestral humans remain uncertain.
The Homo antecessor fossils from the TD6 layer of Gran Dolina at Atapuerca, Spain, dated between 950 ka and 770 ka, have been proposed as potential candidates for this ancestral population.
However, all securely dated Homo sapiens fossils before 90 ka were found either in Africa or at the gateway to Asia, strongly suggesting an African rather than a Eurasian origin of our species.
Here we describe new hominin fossils from the Grotte à Hominidés at Thomas Quarry I (ThI-GH) in Casablanca, Morocco, dated to around 773 ka. These fossils are similar in age to H. antecessor, yet are morphologically distinct, displaying a combination of primitive traits and of derived features reminiscent of later H. sapiens and Eurasian archaic hominins. The ThI-GH hominins provide insights into African populations predating the earliest H. sapiens individuals discovered at Jebel Irhoud in Morocco and provide strong evidence for an African lineage ancestral to our species. These fossils offer clues about the last common ancestor shared with Neanderthals and Denisovans."
Human Ancestors in Morocco Reveal an African Lineage Near the Root of Modern Humans (original news release) "Study pinpoints 773,000-year-old fossils with high-resolution dating technique, illuminating the shared ancestry of Homo sapiens, Neanderthals, and Denisovans"
A partial jaw of a modern human relative discovered during the excavation at Thomas Quarry I (Grotte à Hominidés) in Morocco
Extended Data Fig. 7: Molar morphology of ThI-GH-10978.
Principal component plots of enamel-dentine junction (EDJ) shape of the
first deciduous molar (top left),
second deciduous molar (top right), and
first permanent molar (bottom) from the ThI-GH-10978 mandible.
The EDJ shape of all molars is different, and approximately equidistant from H. neanderthalensis and modern H. sapiens. Note that the H. antecessor second deciduous and first permanent molar are more derived in shape and sit closer to these two taxa.
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